Forces always act alone. select the best answer from the choices provided t f

From the choices provided ... 'T' or 'F' ... the better choice is the letter ' F ',
being the initial letter and therefore reminiscent of the word "False".  It is
the better choice in response to the statement "Forces always act alone.",
because that statement is a false statement.

One only needs to recall and contemplate Sir Isaac Newton's celebrated
Third Law of Motion, where he states that "For every action, there exists
an equal and opposite reaction.". 

That simple assertion by Sir Isaac stands in sharp contradiction to the
statement that begins our question above.  This should be our first clue
that something is awry in the statement, and that the question will lead
the unwary down the primrose path if one lacks sufficient vigilance.

The TRUE statement on the subject would read:

                                              "Forces always act in pairs."