Answer:
A. melde, freiwillig
Explanation: all of the other multiple choice option make no contextual sense.
For example 'B' does not work based on the grammar and even the sound of it should raise suspicion „Ich habe mich vor bei einem Waisenhaus“ would be saying I have me by a orphanage. Here you can see clearly the error. You can apply the same principal to the other two... :)