Option A: Incorrect. Linearly polarized antenna isn't effective - it's more affected by spin modulation and Faraday rotation. Linear polarization isn't effective. Option C: Incorrect. Isotropic antenna isn't practical - circularly polarized antennas are used to minimize effects. Isotropic isn't practical. Option D: Incorrect. Log-periodic dipole array isn't the solution - circularly polarized antennas minimize the effects. Log-periodic isn't the solution.