Dynamic programming is most effective when a problem exhibits overlapping subproblems, meaning the same subproblems are solved multiple times in the process. If a problem does not have this characteristic, dynamic programming may not offer significant advantages over other approaches like recursion or greedy algorithms. Additionally, for problems with very small input sizes, the overhead of dynamic programming (such as building tables or memoization arrays) might outweigh the benefits, making simpler algorithms more suitable.

A deadlock occurs in multithreading when two or more threads are unable to proceed because each is waiting for the other to release a resource, resulting in a standstill where no progress can be made. This can lead to system hangs or crashes.

The CAP theorem is crucial in understanding the limitations of distributed systems. It states that in the presence of a network partition, a distributed system can only guarantee either Consistency or Availability, not both. NoSQL databases often sacrifice Consistency (CP) for better Availability and Partition tolerance (AP).

Mutex and semaphore are both synchronization mechanisms, but they serve different purposes. A mutex ensures mutual exclusion, allowing only one thread to access a resource at a time, while a semaphore can allow multiple threads to access multiple resources concurrently. Mutexes typically use binary values (0 and 1) to signal resource availability, while semaphores can have a count greater than 1, allowing for resource allocation based on available counts.

The correct option is Single Responsibility Principle. This principle suggests that a class should have only one job or reason to change, leading to more modular, maintainable, and understandable code.

In Agile methodologies, estimating the effort required for each user story or task is commonly referred to as "Story Pointing." Story Pointing involves assigning relative values (such as story points) to different tasks or user stories, based on their complexity, risk, and effort required. This practice helps Agile teams plan and prioritize their work effectively during sprint planning sessions. Sprint planning involves determining which user stories and tasks will be tackled in the upcoming sprint, whereas backlog refinement is the ongoing process of reviewing and updating the product backlog. Velocity tracking, on the other hand, is a measure of how much work a team can complete in a sprint, often calculated based on past performance. Therefore, the most appropriate option for estimating effort in Agile is Story Pointing.

Code coverage measures the percentage of code executed by your test suite. To determine this, you can use tools that analyze test results and report on the lines of code covered during testing. This metric helps assess the thoroughness of your testing efforts and identifies areas of the codebase that may require additional test cases for better coverage and quality assurance.

The key difference between deadlock prevention and deadlock avoidance lies in their approaches to handling deadlock situations in operating systems. Deadlock prevention focuses on proactively avoiding deadlock by implementing resource allocation strategies and system design techniques that eliminate the possibility of deadlock occurrence. On the other hand, deadlock avoidance aims to reactively resolve deadlock situations after they occur by detecting them and taking appropriate actions, such as preempting resources or terminating processes to break the deadlock. While prevention aims to stop deadlock from happening in the first place, avoidance deals with managing deadlocks if they occur, making them complementary strategies in ensuring system stability and resource utilization efficiency.

Binary Search is the optimal approach for searching in sorted arrays due to its logarithmic time complexity O(log n). Linear Search is inefficient for large datasets, Hashing may not be suitable for sorted arrays, and Indexing might introduce additional overhead in a distributed system.

IPv6 uses 128-bit addresses, which is a significant increase from IPv4's 32-bit addresses. This expansion allows for a much larger number of possible unique addresses, addressing the issue of IPv4 address exhaustion. Therefore, "128" is the correct option.