A file in HDFS that is smaller than a single block size

cannot be stored in hdfs
occupies the full blocks size.
can span over multiple blocks
occupies only the size it needs and not the full block

The correct answer is: D. occupies only the size it needs and not the full block

A file in HDFS that is smaller than a single block size will occupy only the size it needs and not the full block. This is because HDFS stores files in blocks, and each block is a fixed size. If a file is smaller than a block, it will only occupy the space that it needs.

Option A is incorrect because a file in HDFS can be stored even if it is smaller than a single block size.

Option B is incorrect because a file in HDFS will only occupy the space that it needs, even if it is smaller than a single block size.

Option C is incorrect because a file in HDFS cannot span over multiple blocks if it is smaller than a single block size.