The correct options are
C The trees have special glands which can expel salt.
D The roots of the trees in the mangrove forest are above ground level, sticking out of the marsh.
Trees in the marshes have made two adaptations for its survival. The roots of the trees in the mangrove forest are above ground level, sticking out of the marsh. To breathe, the roots grow above ground level. The trees have special glands which can expel salt.