The theme is the writer's view of or comment about the subject. The answer to your question is D. I hope this is the answer that you are looking for and it comes to your help.
Calcium is one of the most important minerals for the human body. It helps form and maintain healthy teeth and bones.
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Function
-Building strong bones and teeth.
-Clotting blood.
-Sending and receiving nerve signals.
-Squeezing and relaxing muscles.
-Releasing hormones and other chemicals.
-Keeping a normal heartbeat.
Tap Root. Plants with a tap root system have a large dominant central root where other lateral roots sprout. These lateral roots are called secondary roots. Examples of plants with taproot system are: sugar beet, parsnip, carrots, radish, dandelion and beetroot.