Given,
(1 + tan θ + sec θ)(1 + cot θ − cosec θ)
⇒(1+cosθsinθ+cosθ1)(1+sinθcosθ−sinθ1)⇒(cosθcosθ+sinθ+1)(sinθsinθ+cosθ−1)⇒cosθsinθ(cosθ+sinθ)2−12⇒cosθsinθcos2θ+sin2θ+2sinθcosθ−1⇒cosθsinθ1+2sinθcosθ−1⇒cosθsinθ2sinθcosθ⇒2.
Hence, option 4 is the correct option.