(05.01 mc) west indian manatees are large aquatic mammals that live in rivers and near shore estuaries, especially in florida. they have two flexible front flippers with three or four toenails, similar to elephant toenails. though they lack hind limbs, manatees have vestigial pelvic bones, as shown in the diagram. manatee and elephant skeletons are shown side-by-side. the manatee, an aquatic animal, has a skeleton that has two large front limbs and two very tiny hind limb bones that do not form actual limbs. the elephant has four large limbs. which of the following answer choices best describes how evidence of the manatee toenails and pelvic bones supports the scientific theory of evolution of these animals? (1 point)

the correct option is option d

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]