Answer: BCC

Explanation:
In each of the groups ABB, CCCDDDD, BBCCC and
DDDDEEEEE, only two letters of the alphabet are used
and each letter is written as many times as its place
value in the alphabet. This pattern is not followed in the
group BCC.

Answer: VWYZ   

Explanation:
 K+2M +1 N-2L, P+2R+1S"2Q, V +1W+2Y+1 Z, J+2L+1M"2K and
WVYX. Except VWYZ, all the other groups follow
similar pattern.

Answer: UAWY 

Explanation:

0+2Q-4M+6S, U +6A-4W+2 Y, N +2 P- 4 L +6 R, B+2D-Z+6F and
F+H~4D*6J. Except UAWY, all other groups follow
similar pattern.

Answer: I91

Explanation:
In each of the groups B4, D16, E25 and F36 the
number is the square of the position value of the letter.
This pattern is not followed in 191.

Answer: Chameleon

Explanation:
 Crocodile, Turtle, Alligator and Frog are amphibians, while Chameleon is a terrestrial animal

Answer: Trap

Explanation:
Part, Cart, Dart and Mart are rhyme words, but Trap
does not sound similarly.

Answer: Baseball 

Explanation:
Boxing, Chess, Wrestling and Squash are individual events, while Baseball is a team event

Answer: Plank 

Explanation:
Walk, Talk, Drink and Lick are verbs, but not plank.

Answer: EECRALS 

Explanation:
The letters in the word are jumbled. The words are
WHEAT, RICE, J.OWAR, CEREALS and BAJRA.
WHEAT, RICE, JOWAR and BAJRA are different
entities of the class CEREALS.