Usually, the baby's eyes will open around 26-28 weeks gestation.
The heart develops around week five, and begins to beat at the end of the 5th week. A heartbeat via ultrasound by 6 weeks, by 10-12 weeks you should hear the heartbeat with a Doppler device. A heartbeat usually won't be detected at 4-5 weeks of pregnancy.
Preparation for childbirth begins anywhere from 30-32 weeks during the process called lightening (the baby turns to a head-down position), however, the baby can flip to the head-down position, then flip again, and so on.
The formation of hair and eyelashes begins during week 22, so the answer is B. Formation of hair and eyelashes.
The Toxic Substances Control Act requires that, before manufacturing a new chemical in bulk, manufacturers must submit a pre-manufacturing report’ to the EPA in which the environmental and human health impacts of the substance are assessed (including those that may derive from the ultimate disposal of the chemical). Depending on the results of the assessment, the manufacturer may be required to test the effects of the product on living things. Following the results of the testing, a product’s uses may be restricted or a product may be kept off the market altogether.