Your audience can be anybody, children, adults, or any specific group of people. The audience is your reader.
D.
He carried the cooler to the car.
A sentence fragment means a part of a sentence, that is, something that cannot function independently as a sentence.
the correct answer here is "<span> When we stopped by the garden" - option C - it needs more information, information of what happened when we stopped by the garden</span>
It means they are physician fine but mentally they feel down or a feeling of low self esteem or simply being over worked.