Answer:
Option A, most closely related to mammals
Explanation:
Insects like arthropods and molluscs have an open circulatory system and thus do have a distinguishable heart. Fish has two chambered heart. Reptiles have three chambered heart. Amphibians too have a three chambered heart.
All mammals and fish have four chambered heart. The right and left sides of the chambers have restricted entry and hence remain intact from each other
Hence, option A is correct
Among the ones listed above, the statement that best describes the way that the periodic table is arranged is "<span>The nonmetals are grouped together, which the exception of hydrogen.</span>" It can be seen that all of the nonmetals are placed on the far right of the periodic table except for hydrogen. They do not belong in a single column and are separated from the metals by the metalloids. Moreover, the elements are placed in the periodic table in increasing atomic number.
