【单选题】In response to foreign organisms, humans produce a variety of antibodies that can bind to the organism. In the production of human antibodies, which one of the following can cause the production of di...
A.
Pretranscription processing of hnRNA
B.
Removal of introns from hnRNA
C.
Addition of a cap to the 5 ′ -end of hnRNA
D.
Addition of a cap to the 3 ′ -end of hnRNA
E.
Alternative sites for synthesizing the poly(A) tail
【判断题】Imposition of trade barriers by one country can cause other countries to retaliate, and may lead to a trade war in which all countries raise high import barriers.