Answer:
The correct answer would be "Myosin heads attach to sites on actin filaments".
The muscle cell or myofibril consists of two types of protein filaments namely; actin (thin filament) and myosin (thick filament).
The myosin heads attach to the binding sites on the actin filaments and pull it towards the M-line in order to produce contraction.
The hydrolysis of ATP provides energy for this contraction cycle.
The picture it’s not clearly
In the adults, the growth rate slows with age. The healing mechanism of the different cells if damaged is different than that of the younger ones. If a cartilage is damage in the adults, the chondrocytes which are still surviving secrete more extracellular matrix in order to heal the damaged cartilage. The chondrocytes cells are present in the cartilage, and they function to maintain the cellular matrix of the cartilage.
It is Choice B "by drinking water and other liquids"