Which of the following is INCORRECT?

$q,$ If the bond is purchased and held to maturity, the bondholder's $q,($yield to maturity$)$ will not change, regardless of what happens to interest rates.

If interest rates rise, the price of the bond will decrease.

Default risk is influenced by the issuer's financial strength and the terms of the bond contract including whether collateral has been pledged to secure the bond.

A $15-$year coupon paying bond has the duration longer than $15$ years.