Given data:
- Relative density of concrete = 2.5
- Safe allowable stress of foundation material = 3.87 MPa
- Uplift force is not considered

To find: Maximum height of low gravity dam of elementary profile

Assumptions:
- The weight of the dam is uniformly distributed
- The dam has rectangular cross-section
- The dam is made of homogeneous material
- The dam is not subjected to any lateral pressure

Formula used:
- Pressure at any depth h = γh
- Moment of resistance of the dam = (1/6)ρbLh^2, where ρ is the relative density of concrete, b is the width of the dam, L is the length of the dam, and h is the height of the dam
- Maximum bending moment = (1/2)ρbLh^2
- Maximum allowable bending moment = (1/6)fcbLh^2, where fcb is the safe allowable stress of foundation material

Calculation:
- The weight of concrete = γV, where γ is the density of concrete and V is the volume of concrete
- The density of concrete = γc/γw, where γc is the mass density of concrete and γw is the mass density of water
- γc = ρc.g, where ρc is the density of concrete and g is the acceleration due to gravity
- The density of water = 1000 kg/m^3
- The acceleration due to gravity = 9.81 m/s^2
- The relative density of concrete = ρc/ρw = 2.5, where ρw is the density of water
- Solving for ρc, we get ρc = 2.5 x 1000 kg/m^3 = 2500 kg/m^3
- Solving for γc, we get γc = 2500 x 9.81 N/m^3 = 24525 N/m^3
- Let the height of the dam be h
- The cross-sectional area of the dam = bh
- The volume of the dam = AL, where A is the cross-sectional area of the dam and L is the length of the dam
- Solving for L, we get L = V/(bh)
- The maximum bending moment = (1/2)ρbLh^2
- The maximum allowable bending moment = (1/6)fcbLh^2
- Equating the two, we get (1/2)ρbLh^2 = (1/6)fcbLh^2
- Solving for h, we get h = √(3fcb/ρb)
- Substituting the given values, we get h = √(3 x 3.87 x 10^6 N/m^2 / (0.5 x 2500 N/m^3)) = 112.7 m
- The maximum height of the low gravity dam of elementary profile made of concrete of relative density 2.5 and safe allowable stress of foundation material 3.87 MPa without considering the uplift force is about 113 m (rounded off to the nearest integer)

Therefore, the correct answer is '113'.