My trip to Texas was Fantastic.
Explanation:
relative clause
it modifies noun phrase by some grammatical tools
example
my friend who is coming from America is coming to the dinner
here who is used to indicate the noun phrase
subject verb agreement
A subject and a verb must agree, even when other words or phrases come between them.
example
The flock of geese is flying south for the winter.
The subject is flock, so the verb should be is flying.
I would say A but D could also be said softly
a. Employee complaints and d. Safety conditions
The correct answer is the first option, 'Two teams, the Tomcats and the Huskies, battled for the city championship', because that is the only example which contains an appositive phrase, 'the Tomcats and the Huskies'.