When the stem of vibrating tuning fork is pressed on a table, the tabletop starts vibrating. These vibrations are definitely an example of:

forced vibrations

Reason — When the stem of a vibrating tuning fork is pressed against the top of a table, the tuning fork produces forced vibrations in the table top as the table top has a much larger vibrating area than the tuning fork, so the forced vibrations of the table top send forth a greater energy and produces a louder (or more intense) sound than that produced by the tuning fork.