The answer is A. <span>effective length of the tube
In wind instrument, the effective length is not the actual length of the instrument but only the length that the finger holes manage to cover.
The more holes it managed to cover, the higher frequency of vibration it might able to produce, which lead to higher pitch of the instrument.</span>
Pigments absorb light used in photosynthesis.Set of wavelengths that a pigment doesn't absorb are reflected.
Humans' internal body temperature is a great example of homeostasis. When an individual is healthy, his or her body temperature retains a temperature 98.6 degrees Fahrenheit. The body can control temperature by making or releasing heat.