Consider the following four measures (a - d ) that could be taken to successfully grow chickpea in an area where bacterial blight disease is common :

Question

(a) Spray with Bordeaux mixture

(b) Control of the insect vector of the disease pathogen

(c) Use of only disease free seeds

(d) Use of varieties resistant to the disease

Which two of the above measures can control the disease ?

 

$\begin {array} {1 1} (1)\;a\: and \: d & \quad (2)\;b\: and \: c \\ (3)\;a\: and \: b & \quad (4)\;c\: and \: d \end {array}$