A. If you intentionally lied on the application for the coverage and it was a pre-existing condition prior to placing it in force and you're still within the first 2 years of the policy (the contestability period), the carrier could rescind the coverage if it's discovered. Once the contestability period has expired, the carrier cannot rescind a policy due to misinformation on an application.
Other than the above situation, the only way a carrier can cancel your policy is if you don't pay your premiums (the coverage lapsing as a result). If the condition developed after the policy was placed in force, the carrier cannot cancel your policy.