To answer this question, you need to understand verb forms and sentence structure.
The sentence is questioning the reason for insisting on something related to Cambodia. In this case, the verb form that correctly fits the sentence is the gerund form, which is created by adding "-ing" to the base form of the verb.
Let's go through each option to understand why it is correct or incorrect:
Option A) going - This option is correct because it uses the gerund form "going," which functions as a noun in the sentence.
Option B) to go - This option is incorrect because it uses the infinitive form "to go," which is not suitable in this context.
Option C) will go - This option is incorrect because it uses the future tense "will go," which changes the meaning of the sentence.
Option D) to be going - This option is incorrect because it uses the infinitive form with the progressive aspect "to be going," which is not necessary in this sentence.
The correct answer is A) going. This option is correct because it uses the appropriate gerund form to convey the meaning of insisting on something related to Cambodia.