Q35. The number of species from the following that have pyramidal geometry around the central atom is $\_\_\_\_$ . $\mathrm { S } _ { 2 } \mathrm { O } _ { 3 } ^ { 2 - } , \mathrm { SO } _ { 4 } ^ { 2 - } , \mathrm { SO } _ { 3 } ^ { 2 - } , \mathrm { S } _ { 2 } \mathrm { O } _ { 7 } ^ { 2 - }$\\
(1) 4\\
(2) 3\\
(3) 2\\
(4) 1