In cell cycle, which stage is also called the resting phase?
A. S phase
B. Telophase
C. Cytokinesis
D. Interphase

Hint: Firstly we need to know what the cell cycle is. A cell cycle is a step by step process that takes place in a cell when it grows and divides. A cell spends most of its time in interphase. During this time it grows and replicates its chromosomes and gets prepared for the cell division process. The cell then leaves the interphase. Then it undergoes mitosis and completes its cell division process. The resulting new cells are known as daughter cells. Then each of the daughter cells enters into their own interphase and initiates a new round of the cell cycle.

Complete answer:
The interphase of the cell cycle is also called the resting phase. 90% of the cell cycle is shaped by interphase. Interphase is the phase of the whole cell cycle in which the cell spends and performs the majority of its time. Then in preparation for the cell division process it increases in size. Interphase is also considered to be the living phase of the cell cycle. In this phase the cell gets nutrition, then it grows and reads its DNA and conducts other normal cell functions.
So, the option D ‘Interphase’ is the correct answer.

Additional Information:
Option A - S phase: S phase or Synthesis phase is one of the three phases of the interphase of the cell cycle in which DNA is replicated. As exact duplication of the genome is critical to success, the processes that arise during Synthesis phase are firmly regulated and extensively conserved.
Option A ‘S phase’ is not the correct answer.
Option B – Telophase: Telophase is the finishing stage in both meiosis and mitosis in a eukaryotic cell. Throughout this phase the effects of prophase and pro-metaphase are reversed.
Option B ‘Telophase’ is not the correct answer.
Option C – Cytokinesis: It is the part of the cell division. Throughout this part the cytoplasm of an eukaryotic cell divides into two daughter cells. Cytoplasmic division starts during or after the late steps of nuclear division in mitosis and meiosis. It is the part of M Phase or Mitotic Phase.
Option C ‘Cytokinesis’ is not the correct answer.

Note:
Different cells take different time lengths to complete the cell cycle. A human cell might take about 24 hours to divide. But fast-cycling mammalian cells, such as the ones that line the intestine can complete a cell cycle every 9-10 hours when they are grown in culture. Various kinds of cells also split their time of each phase between cell cycle phases in different ways.