Correct option is D
Option (d) is the correct meaning of the given idiom.
A greenhorn means someone who is inexperienced or naive. (अनुभवहीन व्यक्ति)
Example: As a greenhorn, he made several mistakes in his first job.
Other related idioms and their meanings:
·
Wet behind the ears – Inexperienced.
·
Newbie – A beginner.
·
Rookie – A person new to a job or activity.