By recycling textbooks, the cost of the books will be reduced greatly, and there is no doubt that it will unload some ________ of the families and students.
本题主要考查词义辨析。句意：通过回收教科书，书的成本将会大大地减少，并且毫无疑问的是将会给一些家庭和学生卸下负担。A项意为“预 算”，B项意为“自助餐”．C项意为“繁荣”．D项意为“负担”，由题意可知，本题选D。