Answer:
Which mission did Sally Ride fly for NASA?
Explanation:
A direct object is a noun that denotes the <u>recipient</u> of the action of a verb.
In the sentence 'Which mission did Sally Ride fly for NASA?', the word mission is the recipient of the action of the verb fly (used together with the helping verb did to show that this action happened in the past.)
If you are using it as a title for some one yes, if not then no.
The adverb clause would be since you insist.
The word it modifies is I will tell you my secret.
