Option 3 suggests using atomic operations and compare-and-swap (CAS) instructions for lock-free updates to the linked list. This approach ensures data consistency in a real-time environment without introducing overhead from locking mechanisms or copy-on-write strategies. Atomic operations guarantee that updates are performed atomically, preventing race conditions and maintaining efficiency in frequent data updates.

A mutex is a synchronization primitive that allows only one thread to access a resource at a time, preventing data races and ensuring thread safety.

Batching is a technique used in RESTful APIs where multiple requests are combined into a single request to improve efficiency and reduce overhead. This is particularly useful when a client needs to make several related requests to the server, as it reduces the number of round-trips required between the client and the server, thereby improving performance.

A singly linked list is best suited for implementing a stack because it only requires a pointer to the top element, allowing for efficient insertion and removal operations at the top of the stack.

Merge sort is preferable over quicksort when dealing with large input sizes due to its guaranteed O(n log n) time complexity, which is advantageous over quicksort's worst-case O(n^2) time complexity.

The correct option is ".dockerfile." Docker uses Dockerfiles, which are plain text configuration files with a specific syntax, to define the steps needed to create a container image. These files specify the base image, environment variables, dependencies, and commands to run when the container starts. Dockerfiles are essential for building reproducible and version-controlled containerized applications, making it easier to manage and scale container deployments.

Using the accept attribute in the tag allows specifying the allowed file types (MIME types) that users can upload. This provides client-side validation to ensure that only files of specified types are accepted. The File API, on the other hand, allows accessing file metadata, including size. Using typeof is not suitable for file type validation. The FileReader API is used to read file content, not metadata.

In merge sort, the merge operation combines two sorted arrays into a single sorted array. This is a crucial step in the merge sort algorithm, where the sorted subarrays from the divide step are merged back together to create a larger sorted array. The merging process compares elements from both arrays and arranges them in ascending or descending order, depending on the sorting order specified.

The Banker's algorithm is used in operating systems to manage resources such as CPU cycles, memory, and input/output devices. It simulates the allocation of resources to processes and ensures a safe state to avoid deadlock.

Leveraging frameworks like Next.js or Angular Universal for SSR ensures that search engines receive fully rendered pages, enhancing SEO. Custom SSR logic can be complex, and static site generation may not be as dynamic for SEO purposes.

NAT operates at the network layer of the TCP/IP model. It allows a network to use private IP addresses internally while communicating with the internet using a single public IP address. NAT modifies the source IP address in outgoing packets to the public IP address and maintains a translation table to route incoming responses back to the correct internal device.

Query optimization is the process of rearranging the execution plan of a query to enhance its performance. This optimization can involve various techniques such as selecting appropriate indexes, restructuring the query, or using hints to guide the database optimizer in choosing the most efficient execution path. By optimizing queries, database administrators and developers aim to reduce query execution time and resource consumption.