The correct option is C AD+BE+CF<AB+BC+CA
In triangle ADB,
AD+BD>AB
In triangle ADC,
AD+DC>AC
In tringle BEC,
BE+EC>BC
In tringle BEA,
BE+AE>AB
In traingle, CFA,
CF+FA>AC
In traingle, CFB,
CF+FB>BC
Add all the inequalities,
2(AD+BE+CF)+AB+BC+CA>2(AB+BC+CA)
2(AD+BE+CF)>AB+BC+CA
or AD+BE+CF<AB+BC+CA