The most suitable options to fill the gaps in the sentence are ; Aptitude and Positing. The word aptitude may be described as a natural Penchant or desire towards a particular craft, skill or subject. Hence, we can say Farnell has a natural aptitude for science, that his he loves science naturally.
Positing may be explained as the act of putting forward or suggesting something maybe an hypothesis which could then be worked on. Therefore, Darnell's aptitude for science may be seen as a reason why he enjoys positing new theories to other staffs.
