1. A system design support apparatus comprising: a storage device configured to store a first table in which design information elements of a system designed in the past and requirements to be achieved by the design information elements are stored in association with one another, and a second table in which aptitudes of combined use of a plurality of the design information elements included in the first table are managed with aptitude ranks assigned on the basis of track records of the combined use; and a processing unit configured to identify first design information elements achieving a plurality of requirements concerning a system to be newly designed, by using the first table in the storage device, when a plurality of the first design information elements are identified for a first requirement among the plurality of requirements as a result of the identification, to refer, in the second table in the storage device, to the aptitude rank of combined use of each of the plurality of the first design information elements and a design information element identified for a second requirement different from the first requirement among the plurality of requirements, and thereby to identify the first design information element establishing a combination at a higher aptitude rank among the plurality of the first design information elements, and to output the first design information elements thus identified for the plurality of requirements to a predetermined device.