I believe B. Is the correct choice. When using the word " Oh" in a sentence, it usually contains a comma before another statement.
Answer:Which one is in bold? It doesn't appear in the question.
Explanation:
Language is a system of signs represrnting ideas to convey a message. Those symbols, which are words can be arbitrary, ambiguous, abstract representations of other phenomena. Words are not intrinsically connected to what they represent. Meanings of words can shift over time. The arbitrary character allows us to invent new words.
Language is ruled guided, simply put, verbal communication is guided by unspoken but broadly understood rules.
So I would say that option A, C and D are correct.
Meanwhile, I think that option B is incorrect since a mean of communication is understood as the tool and technology employed in order to convey a message, exchange information, ideas.
I'm pretty sure it's the last one; Everyone was having a wonderful time at the party, because the present tense helps it feel more active.