A plant that was grown in the dark continuously would: . a. not be able to take in CO2 without sunlight.
b. remain healthy because plants have stored materials in their roots that can provide what the Calvin cycle needs.
c. not be able to split water to provide NADH.
d. continue to photosynthesize because to in carbon dioxide, the only outside input to the Calvin cycle, does not require sunlight.

c. not be able to split water to provide NADH.

Explanation:

Photosynthesis, which is the process by which plant species obtain their energy, occurs in two stages viz: light dependent phase and light independent phase. The light dependent phase of photosynthesis requires the energy from sunlight, which is captured by the chlorophyll pigments in the leaves of the plant.

The light energy captured by the chlorophyll is used to split water molecule in a process called PHOTOLYSIS OF WATER. Overall, ATP and NADH (electron donor) are products of the light dependent stage, which enters the next stage to complete the photosynthetic process.

Therefore, a plant that was grown in the dark i.e. no access to light, continuously would not be able to capture light energy and hence not be able to split water to provide NADH.

thinking it would be physical characteristics