Give an account of the effects of timber extraction, mining dams on forests and tribal
people

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen

Ithink its the 3rd one

The "highest" point is a single point. 
there can't be more than one "highest" point.
it's not possible for every point on a line to be the "highest" one.