Mixotrophic nutrition is observed inSelect an answerASulphur bacteriaBChlamydomonasCEuglenaDHouse fly

The correct answer is CEuglena.

Euglena is a type of single-celled organism that is often green from its chlorophyll. This organism is unique because it is both a heterotroph, meaning it can consume food as animals do, and an autotroph, meaning it can create its own food as plants do. This type of nutrition is known as mixotrophic nutrition.

Here are the steps to answer this question:

1. Understand the question: The question is asking which of the given options exhibits mixotrophic nutrition. Mixotrophic nutrition is a type of nutrition where an organism can use different sources of energy and carbon, acting as both a photoautotroph and a heterotroph.

2. Eliminate incorrect options: Sulphur bacteria are chemotrophic, meaning they get their energy from chemical reactions. House flies are heterotrophic, meaning they get their energy from consuming other organisms. Chlamydomonas is a type of algae that is typically autotrophic, meaning it gets its energy from sunlight.

3. Select the correct answer: Euglena is known to be mixotrophic. It can photosynthesize when light is available, acting as an autotroph, and consume food by heterotrophy when light is not available. Therefore, the correct answer is CEuglena.