A simple presentence is needed to form a meaningful sentence that needed to be performed by the nouns (subjects).
For example, in the above case, all the members (noun) of the group (pronoun) want (simple present tense) to be seated together is the correct sentence formation without any grammatical error.
Thus, the options (c), (d), and (a) are incorrect.
For example, in the above case, all the members (noun) of the group (pronoun) want (simple present tense) to be seated together is the correct sentence formation without any grammatical error.
Therefore, the correct option is –