Correct option is B
Citrus tristeza is caused by the Citrus tristeza virus (CTV), which leads to a range of symptoms in citrus plants, including stem-pitting. This disease affects the vascular tissues of the plant, causing a decline in the tree's health and production.
It leads to decline, yellowing, and dieback in citrus trees.
Transmission is primarily through aphids.
Citrus exocortis: Caused by a viroid, it leads to stem-pitting, but Citrus tristeza is the more common and serious disease related to this symptom.
Citrus greening: Caused by bacteria, this disease leads to yellowing and misshapen fruit.
Citrus canker: Caused by the bacterium Xanthomonas axonopodis, this disease affects the fruit and leaves.
