In 2010 a new type of life form was found in california's lake mono. the microbe found has a variation in the structure of its dna. dna usually consists of nitrogen bases, sugars and phosphates. however, this newly-discovered microbe uses arsenic if phosphorus is not available. this fact might lead to the discovery of

a) new dna sequences in mammals.

b)
new dna structures in mammals.

c)
possible life in non earthlike environments.

d)
phosphorus being unnecessary for dna structures in mammals.

The correct answer is-

C) possible life in non earthlike environments.

As per the information provided in the question, the microbe found in   California's Lake Mono has a variation in the structure of its DNA as they use arsenic ( if phosphorous was not available) to incorporate in the nucleotides of their DNA.

This indicates the possibility of life form in non earth like environment because life forms that originated on earth like environment possess carbon, nitrogen, oxygen, and phosphorous ( that is composed of four basic elements).

But life can also be formed in an environment that lacks phosphorous ( for instance, DNA formed in microbes utilized arsenic in absence of phosphorous, indicating variation in their structure).

Thus, option C) is the right answer.

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