Oxidative phosphorylation occurs in mitochondria, while photophosphorylation occurs in chloroplasts to produce ATP.
so the correct incorrect answer is mitochondria help in phosphorylation.

< b="" />Incorrect statement regarding plant cell:
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< li="" />Mitochondria help in photophosphorylation
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< b="" />Explanation:
< h3="" />Leucoplasts:
Leucoplasts are a type of plastid found in plant cells. They are responsible for the synthesis and storage of starch, oils, and proteins. Unlike chloroplasts, which contain pigments and are involved in photosynthesis, leucoplasts lack pigments and are not involved in the production of energy. Leucoplasts are bound by two membranes and are typically found in non-green tissues such as roots, fruits, and seeds.

< h3="" />Golgi Body:
The Golgi body, also known as the Golgi apparatus, is an organelle found in plant and animal cells. It is involved in the processing, packaging, and secretion of various substances produced by the cell. The Golgi body receives proteins and other molecules from the endoplasmic reticulum and modifies them before packaging them into vesicles for transport to their final destination. Therefore, it is responsible for the packing and secretion of cell secretions.

< h3="" />Mitochondria:
Mitochondria are double-membraned organelles found in plant and animal cells. They are often referred to as the "powerhouses" of the cell because they generate energy through cellular respiration. Mitochondria play a crucial role in the production of adenosine triphosphate (ATP), which is the main source of energy for cellular activities. However, mitochondria are not involved in photophosphorylation, which is the process of converting light energy into chemical energy during photosynthesis. Photophosphorylation occurs in chloroplasts, not mitochondria.

< h3="" />70S Ribosomes:
Ribosomes are cellular structures involved in protein synthesis. In plant cells, ribosomes can exist in two forms: 80S ribosomes and 70S ribosomes. The "S" in ribosomes refers to the Svedberg unit, which is a measure of the sedimentation rate of the ribosomes during ultracentrifugation. The Svedberg unit takes into account the size, shape, and density of the ribosomes.

The statement that the "S" indirectly measures the density and size of 70S ribosomes is correct. The higher the S value, the larger and denser the ribosomes are. The 70S ribosomes are found in the cytoplasm of plant cells and are responsible for protein synthesis.

Therefore, the incorrect statement regarding plant cells is that mitochondria help in photophosphorylation.