The correct relation is [CPMT 1986; MP PET 1981; AFMC 1996]

• A.            \[B=\frac{{{B}_{V}}}{{{B}_{H}}}\]                                    
• B.            \[B={{B}_{V}}\times {{B}_{H}}\]
• C.            \[|B|=\sqrt{B_{H}^{2}+B_{V}^{2}}\]                            
• D.            \[B={{B}_{H}}+{{B}_{V}}\] (Where \[{{B}_{H}}=\]Horizontal component of earth's magnetic field; \[{{B}_{V}}\]= Vertical component of earth's magnetic field and B  = Total intensity of earth's magnetic field)