Select the most appropriate option to fill in the blank.
Arun and his friends are like _______________________; they always agree on everything.

Correct option is B

Option (b) is the correct meaning of the given idiomatic sentence.
Idiom: Two peas in a pod: Used to describe two people who are very similar in appearance, behavior, or thinking. (दो लोग जो पूरी तरह से एक जैसे हों)
Example: My cousins are like two peas in a pod; they even dress the same.
Other idioms with similar meanings:
Birds of a feather (flock together) – People with similar interests or traits tend to associate with each other.
Cut from the same cloth – Very similar in behavior, character, or thinking.
Like father, like son – A child closely resembles or behaves like their parent.