AS we are supposed to find
[tex] \text{Types of concurrent constructions needed to find the orthocenter of a triangle} [/tex]
[tex] \text{As we know that the orthocentre is}\\\text{as the point of intersection of altitudes from the vertices}\\ [/tex]
[tex] \text{Hence the types of concurrent construction required will be }\\\text{Intersection of the lines drawn from the vertex of the triangle and }\\\text{perpendicular to its opposite sides.} [/tex]
Hence the correct option is A.
[tex] \text{Intersection of the lines drawn from each vertex of the triangle }\\
\text{and perpendicular to its opposite side.}\\ [/tex]
