If 123 means "very hot day", 356 means "hot filtered coffee", 289 means "day and night". The numeral that stands 'very' is:

a. 5

b. 2

c. 1

d. 9

Option C.

Step-by-step explanation:

It is given that

123 means "very hot day" ... (1)

356 means "hot filtered coffee" ... (2)

289 means "day and night" ... (3)

In (1) and (2), common number is 3 and common word is hot.

hot = 3

In (1) and (3), common number is 2 and common word is day.

Day = 2

In (1) the remaining number is 1 and remaining word is very.

very = 1

Therefore, the correct option is C.