Keeping all strings JNI android to protect from reverse engineering?

This is how i am keeping strings in JNI

extern "C" JNIEXPORT jstring JNICALL
Java_com_galaxy_mars_moon_MainActivity_getDefaultNegative(JNIEnv* env, jobject)
{
std::string defaultNegative = "Cancel";
return env->NewStringUTF(defaultNegative.c_str());
}

And i call this native function from java class.

My Questions are :

1. Would it be able to decompiling person to identify?
2. I uses Proguard too, Does proguard will make obfuscate code from it?
3. Will it be converted to .so file and will it be readable to decompiling person?

Thank you in advance. I hope someone will throw more light on it