‘Master control of the cell’ or ‘cell brain’ is
nucleus
The correct option is C.
Explanation of the correct option :
1. Nucleus is a large spherical organelle consisting of the genetic material of an organism.
2. It is the central part of the cell that controls and conducts all the activities of the cell.
3. It keeps genetic information in the form of DNA and chromosomes, controls the metabolism of the cell, carries out protein synthesis, etc.
4. All the metabolic activities of the cell are coordinated by the nucleus. It makes a cell 'think.' Hence,' Master control of the cell' or 'cell brain' is the nucleus.
Explanation of the incorrect options :
Option A :
Mitochondria provide the site for cellular respiration and thus release energy in this process. Hence mitochondria are known as the 'Power House of the cell.'
Option B :
Ribosomes are involved in the process of protein synthesis and hence are called protein factories of the cell.
Option D :
Plastids are exclusively found in plants that involve different pigments for photosynthesis, imparting colours to fruits and flowers and storage.
Final answer: 'Master control of the cell' or 'cell brain' is the nucleus.