Choose the group of letters which is different from others.

Answer: Option D

Explanation:

All other groups contain consecutive letters.

Answer: Option B

Explanation:

All other groups are consecutive letters in reverse order.

Answer: Option D

Explanation:

In all other second is a part of first.

Answer: Option A

Explanation:

All except cot are part of bed-spread.

Answer: Option A

Explanation:

All except Brigadier are ranks of Navy, while Brigadier is a rank of army.