B. subcutaneous skin layer
Two criteria that would identify the three muscle tissues are myofibers and nuclei.
There are three types of muscles:
1. Skeletal-Contains many nuclei along the length of the muscle cell. The nuclei are displaced peripherally. The skeletal fibers are arranged parallel. The myofibril is composed of bands.
2. Smooth-This tissue contain spindle-shaped cells with a single central nucleus. Smooth muscle fibers are shorter than skeletal.
3. Cardiac-The fibers of cardiac muscle are not simply parallel. Cardiac muscle fibers are long cylindrical cells with one or two nuclei.
Crossing over<span> occurs </span>between<span> prophase 1 and metaphase 1 and is the process where </span>homologous chromosomes<span> pair up with each other and </span>exchange<span> different segments of their genetic material to form recombinant </span>chromosomes<span>. It can also happen </span>during<span> mitotic division, which may </span>result<span> in loss of heterozygosity. </span>
The answer is Isolation I hope this helps you out