1. A diagnosis support apparatus connected to a display unit and an operating unit, the diagnosis support apparatus comprising: a display control unit configured to cause the display unit to display a plurality of input graphical user interfaces (GUIs) into which a plurality of findings regarding a subject is to be input; an acquisition unit configured to acquire a deduction result of diagnosis for the subject by a deduction unit based on a plurality of findings input through the plurality of input GUIs in response to input from the operating unit; a processor configured to determine, as an effect of at least one input finding, a degree to which the input finding positively or negatively contributes to the diagnosis on the basis of a difference between a probability that the deducing unit deduces a predetermined diagnosis by using the input finding and a probability that the deducing unit deduces the predetermined diagnosis without using the input finding; and a selection unit configured to, based on the determined degree, select at least one finding from the plurality of input findings, wherein the display control unit is configured to cause the display unit to display the at least one finding input through at least one of the plurality of input GUIs and selected by the selection unit together with the plurality of input GUIs so that the at least one selected finding is distinguished from findings input through the at least one of the plurality of input GUIs and not selected by the selection unit.