1 Anne’s father gives her a diary
2Anne and her family go into hiding
3Mr. Van Daan steals bread from the cupboard
4Annes father returns to the attic
5 the residents of the Secret Annex are discovered
P.s if you want more people to answer your questions, try increasing the points. Me answering this pretty hard question was just out of the kindness of my heart.
"The space shuttles is the subject."
Simple formula: find the verb of the sentence then ask the question "who or what performs the verb" and the answer to that question is the SUBJECT of that sentence!
In your sentence; ask the question;
"Who or what have made travel to the International space station convenient and possible?
Answer: The space shuttles (that's your subject)
The correct answer is distinct parts within a larger structure!
hope this helps!!