The correct answer is: D. No error
The sentence “I am thinking of to go to Agra for my cousin’s marriage” is grammatically correct. The infinitive
“to go” is used after the verb “thinking of” to express a purpose or intention. The preposition “for” is used to indicate the reason for the action.The other options are incorrect because they either change the meaning of the sentence or make it grammatically incorrect.
Option A: “I am thinking of” is a phrase that expresses an intention or purpose. If we change it to “I am thinking”, the sentence would mean that the speaker is simply thinking about going to Agra, without any specific intention.
Option B: “to go” is the infinitive form of the verb “go”. If we change it to “going”, the sentence would mean that the speaker is currently in the process of going to Agra.
Option C: “for my cousin’s marriage” is a prepositional phrase that indicates the reason for the action. If we remove it, the sentence would mean that the speaker is thinking of going to Agra, but we would not know why.