State true(T) or false(F) to the given statements and select the correct option.
( a ) Annual rings are distinct in plants growing in temperate regions.
( b ) Lenticels occur in most woody trees and permit the exchange of gases.
( c ) Due to stelar secondary growth, central cylinder of wood surrounded by secondary phloem is formed.
( d ) The cells of endodermis opposite to protoxylem divide to give rise vascular cambium in dicot roots.