What Deficiency does the below rebus represent?

VIT_MIN

A Japanese ship is sailing in the Indian Ocean. The captain of the ship feels tired and decides to take shower to be rejuvenated. He goes to take the shower after keeping his diamond-studded Rolex watch and gold chain on the table.
When he comes back after 15 minutes, he finds them missing. There are 4 crew members on the ship and he calls them one by one to ask them what they were doing in that duration.

Following are the answers:
1. Crew 'A' who is the cook replies that he was cooking mutton for the crew members.
2. Crew 'B' who is a housekeeper tells that he was sleeping in his room.
3. Crew 'C' who is the engineer says that he was checking on the generator.
4. Crew 'D' who is another housekeeper says that he was correcting the hoisted flag that was put upside down.

It took only a couple of seconds for the captain to find the thief. Can you find the thief too?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

What is the probability of choosing the correct answer at random from the options below?

a) 1/4
b) 1/2
c) 1
d) 1/4

What famous saying does this rebus mean?

COME SERVED <---
COME SERVED
COME SERVED
COME SERVED
COME SERVED

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

What can go up a chimney down, but can’t go down a chimney up?

There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?