(1) According to the graph analysis, in the process of ①, the target sticky end should be cut off with restriction endonuclease, and then connected with DNA ligase.

(2) The modified CpTI gene was introduced into rice somatic cells, and insect-resistant rice plants were obtained by plant tissue culture technology, which reflected the totipotency of plant cells.

(3) A. In genetic engineering, antibiotic resistance genes are often used as marker genes instead of target genes, and A is wrong;

B, genetic engineering generally uses the same restriction endonuclease to treat the target gene DNA and vector DNA, so that they produce the same sticky end, which is beneficial to base complementary pairing and B error;

C. Plasmids are commonly used vectors in genetic engineering. They are small circular DNA molecules, and C is correct.

D. If plant cells are totipotent, fertilized eggs and other somatic cells can be used as recipient cells. D is wrong.

So choose: C.

(4)A, human glycoproteins must be further processed and synthesized by endoplasmic reticulum and Golgi apparatus, that is, glycoproteins need eukaryotic cells, and Escherichia coli is a prokaryote without endoplasmic reticulum and Golgi apparatus, so A is wrong;

B, yeast is a eukaryotic cell, containing endoplasmic reticulum and Golgi apparatus, B is correct;

C, phage is a virus, without cell structure, C error;

D, plasmid is a naked, simple structure, does not depend on bacterial pseudonuclear DNA and self-replicating DNA molecules, and has no cell structure and D error.

Therefore, choose: B.

So the answer is:

(1) target sticky end

(2) Tissue culture

(3)C

(4)B