A radioactive nucleus undergoes a series of decay according to the scheme \[A\xrightarrow{\alpha }{{A}_{1}}\xrightarrow{\beta }{{A}_{2}}\xrightarrow{\alpha }{{A}_{3}}\xrightarrow{\gamma }{{A}_{4}}\] If the mass number and atomic number of A are 180 and 72 respectively, then what are these number for A4 [Roorkee 1986; MP PET 2002; KCET 2003; DPMT 2005]

• A.            172 and 69                             
• B.            174 and 70
• C.            176 and 69                             
• D.            176 and 70