Final answer:
The complementary strand of the given DNA sequence 3′-TCGATT-5′ is 5'-AAGCTA-3'.
Step-by-step explanation:
The complementary strand of DNA can be determined by pairing the nucleotides with their complementary bases. In DNA, adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G). So, for the given sequence 3′-TCGATT-5′, the complementary strand would have the sequence 5’-AAGCTA-3’. This is option 4) 3′-GCTAAA-5′.