Shalu is the daughter of only son of Kartik. Nirupama is the mother of Dev. Yamini’s only son Arun is married to Nirupama. Kartik is paternal grandfather of Dev. How is Kartik related to Arun?

Father

‘+’ means Men’s category

‘–’ means Women’s category

Kartik (+)     -    Yamini (-)

     ↓                       ↓

Arun (+)     -    Nirupama (-)

     ↓                       ↓

  Dev (+)     -     Shalu (-)

     ↓                       ↓

(Kartik is father of Arun)