Soln. It does not make sense to have the patent
strong when it is about to expire or innovation level is
decreasing. So, option c and d is ruled out. It is normal for the
patent to be eligible for strong patent, when it is producing the
innovation before the expiry. What makes the patent strong is, when
it still continues producing meaningful innovation, while reaching
to his expiry date. Hence option a is correct statement, that
states that when a patent is still continuing to produce meaningful
innovation, when a patent is about to expire is correct option.