Fill in the blanks with the most appropriate words.
He has applied _ _ _ _ _ the bank _ _ _ _ _ a loan.
(a)At/for
(b)On/for
(c)For/for
(d)To/on

Hint: In the given question, ‘the bank’ is a place so the first blank will be a preposition of place while the second blank is followed by the purpose of an action (applying for a loan) so, it would be filled by a function word that indicates a purpose.

Complete answer:
A preposition is a word used to link nouns, pronouns, or phrases to other words within a sentence. They act to connect the people, objects, time and locations of a sentence. Prepositions are usually short words, and they are normally placed directly in front of nouns.

Let us consider each blank. The first blank is followed by ‘the bank’.
Option a suggests ‘At’ in the first blank. A bank is a place and for places the preposition generally used is ‘at’. Also, ‘at’ answers the question of where the person has applied (the bank). Now the next blank precedes ‘a loan’ would be filled by the preposition ‘for’ as it indicates the purpose (a loan). Also, the only option that has ‘at’ in the first place is the option ‘a’.
Option b has ‘on’ in the first place and ‘for’ in the second place. While the option for the second blank is correct, the option for the first blank i.e. ‘on’ is incorrect as on is a preposition used when we talk about a surface, like a table, road, etc. rather than for a place. Thus, option ‘b’ is incorrect.
Option c suggests ‘for’ for both the blanks. Using ‘for’ in the first blank would mean that the bank is what the person applied for which is incorrect. The bank is not the purpose, the loan is. Thus, the option ‘c’ is incorrect.
Option d suggests ‘to’ for the first blank and ‘on’ for the second, which is incorrect as ‘on’ is used for indicating the top of a surface like a shelf, table, land, etc. which is not applicable on ‘loan’ and to is used to direct or point to a particular person, thing, direction, etc. Thus, the option ‘d’ is incorrect too.

Therefore, option ‘a’ is the correct answer.

Note: The word ‘for’ is preposition but it is also used as conjunction just like ‘because’ or ‘since’ to indicate the purpose of something (an action)