Which Best Describes What the Map Method Accepts and Emits

Multiple Choice

Which best describes what the map method accepts and emits?

A) It accepts a single key-value pair as input and emits a single key and list of corresponding values as output.
B) It accepts a single key-value pairs as input and can emit only one key-value pair as output.
C) It accepts a list key-value pairs as input and can emit only one key-value pair as output.
D) It accepts a single key-value pairs as input and can emit any number of key-value pair as output, including zero.