How can you prevent data skew in a Hadoop job with uneven key distribution?

What is a common optimization technique to improve Hadoop MapReduce performance?

A. Increase block size

B. Decrease block size

C. Maintain the default block size

D. Use fewer mappers

Which compression codec is commonly used for optimizing storage in Hadoop?

A. Gzip

B. Snappy

C. Bzip2

D. LZO

What is the purpose of Hadoop speculative execution?

A. To handle speculative workloads

B. To minimize resource usage

C. To mitigate the impact of slow-running tasks

D. To speed up task completion

How can data skew in a Hadoop job be addressed for optimization?

A. Increase the number of reducers

B. Decrease the number of reducers

C. Use a combiner function

D. Use a custom partitioner