<span>The correct answer is: d. 1/4; 1/8.
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Baby's head must be large and must grow rapidly because its brain during the first 9 months of growth reaches half of its adult size. So, the head has to (compared to the size of their body) accommodate that brain. Sometimes it is even bigger than one-quarter of full baby’s length.
I believe a possible option for this would be an antibiotic, many specialized kinds interfere with the growth and development of microbes including bacteria.
This is an example of a placebo effect. A placebo is something that seems to be a "real" medical treatment but the truth, it isn't. It could be a pill, an injection, or some other kind of "fake" treatment. What all placebos have in common is that they do not encompass an active substance meant to affect health.