Cancer
Moon, Mars and Jupiter are the most beneficial planets for Cancer Lagna natives. Moon being the Lagna lord is the first rate benefic planet for Cancer Lagna. Mars being the Yogakaraka he is also highly beneficial. But Jupiter is not very supportive for Cancer Lagna unless posited in a good place with aspect or conjunction to either Moon or Mars. Moon alone can confer RY to Cancer natives if posited in Lagna, 10thor in the 11th house. Mars alone also can confer RY if posted in the 7th or in the 10th house. Conjunction of Moon and Mars can constitute RY in any house except Dusthanas (6, 8 and 12). Meanwhile the exchange of houses between Mars and Moon is not good for Cancer born since it will the sign of debilitation for both. Mars in Lagna if subject to cancellation of debilitation can confer good results while Moon in the 5th for Cancer Lagna can never provide good results. Jupiter can also constitute a RY if posited in the 6th or 10th house with Mars or if posited in the Lagna with Moon or Mars. Jupiter causing Hamsa yoga in Lagna or Saturn causing Sasa yoga in the 7th house is not capable of conferring RY to the native while Malavya Yoga caused by Venus in the 4thhouse or 9th house and Sasha yoga caused by Saturn in the 4thhouse can be beneficial to some extent.
To sum up Moon and Mars are very vital in forming RY for Cancer born while Jupiter can be vital on occasions.