Explain why tongue rolling ability is a discontinuous variation

He will be able to roll his tongue, because the 'A' allele is dominant over the 'a' allele. ... Tongue rolling is an example of discontinuous variation: you either can roll your tongue or you can't. Other characteristics, for example height and weight, show continuous variation. People come in all shapes and sizes.

anthropod traits:

a well-developed collarbone

rotating shoulder joints

partially rotating elbow joints

opposable thumb

similar dental formula

i do believe the correct answer would be the third one. location c, because earth is tilted away from the sun at this time

hope this