Correct option is B
The correct meaning of the idiom
"Bread and butter" is
(b) Means of livelihood.
Bread and butter: This idiom refers to the primary source of income or what someone does to earn a living.
Bread and butter in Hindi: आजीविका का साधन।
Example: Writing articles is her bread and butter.
Other related idioms with meanings:
· "Make ends meet" – To manage one's income to cover expenses.
· "Keep the wolf from the door" – To have just enough money to survive.
· "Earn a living" – To make money for daily needs.