Select an incorrect statement regarding secondary growth in dicot stem or root

Options

A. In dicot stem parenchymatous cells of each medullary ray, lying between the intrafascicular cambium of the adjacent bundles divide and become meristematic and form a strip of cambium called the interfascicular cambium.
B. In dicot stem complete vascular cambium is partly primary and partly secondary in origin.
C. In dicot stem the cells of the cork cambium are rectangular and these cut off cells only on out sides.
D. In dicot roots cells of the pericycle become meristematic and give rise to a few layers of thin-walled rectangular cells. These constitute the Cork cambium or phellogen.

Explanation

To determine the incorrect statement regarding secondary growth in dicot stems or roots, we will analyze each option provided in the question step by step.

### Step 1: Analyze the first statement
The first statement claims that in the dicot stem, parenchymatic cells of each medullary ray lying between the intrafascicular cambium of adjacent bundles divide and become meristematic, forming a strip of cambium called the interfascicular cambium.

**Evaluation**: This statement is correct. During secondary growth, the medullary rays differentiate and contribute to the formation of the interfascicular cambium.

### Step 2: Analyze the second statement
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