The grammar analysis and translation as basic procedures appeared in the foreign language learning in the______.

A．16th century

B．17th century

C．18th century

D．19th century

春季植树总是将树枝大量砍去，只留很少的枝芽，这是为了______，在树根扎入泥土，可吸收较多的水分前不至于枯死．