Which of the following represents a compound?

h2o
o-16
h-3
h

The symbol that corresponds to a compound is:

Explanation:

When speaking of a compound, it must be taken into account that it is the combination of two or more totally different elements, so, although in some options numbers such as 3 or 16 are shown, you must recognize that they are several valences of the same element, therefore the only formula that corresponds to a compound is H20 water, which includes hydrogen and oxygen.