What do you call the drugs that bind to the receptor

In the following expression find the missing term:  

Study the given pattern carefully and select the number that can replace the question mark [?] in it.

Select the number from among the given options that can replace the question mark (?) in the following table.

Find the missing letter.

Insert the correct missing number from the choices given below:

Study the given matric carefully and select the number from among the given options that can replace the question mark (?) in it.

What will come in the place of question mark?

Find the missing term :

Study the given pattern carefully and select the number that can replace the question mark (?) in it.

 First row: 84, 42, 49