Within the head of the T4 phage, the _ molecule is present.

Explanation

The T4 bacteriophage contains a double-stranded DNA genome of about 169,000 base pairs. Like all dsDNA, the strands are antiparallel and held together by hydrogen bonds between complementary bases. Inside the phage head, this DNA is packed at very high density in a spool-like, liquid-crystalline arrangement. The DNA is enclosed within a rigid protein capsid, which is made of capsid proteins arranged in an icosahedral lattice with hexamers and pentamers. This structure both protects the genome from the environment and allows efficient injection into the host cell during infection.